Question

6. BSA has the following amino acid profile compared with the average of known vertebrate proteins:

AA	BSA	Average Protein
Phe	4.6%	4.0%
His	2.7%	2.9%
Lys	10.1%	7.2%
Arg	3.9%	4.2%
Trp	0.3%	1.3%
Tyr	3.4%	3.3%

Based upon this data, is BSA a good standard to use in the Bradford assay? Explain your answer.

Answer 1

Bovine Serum Albumin : Bovine serum albumin (BSA) is a serum albumin protein derived from cows. It is often used as a protein concentration standard in lab experiments. . BSA is also commonly used to determine the quantity of other proteins, by comparing an unknown quantity of protein to known amounts of BSA (see Bradford protein assay). BSA is used because of its ability to increase signal in assays, its lack of effect in many biochemical reactions, and its low cost, since large quantities of it can be readily purified from bovine blood .

BSA is a good standard to use in the Bradford assay because dye color development is significantly greater with BSA than with most other proteins. For using a protein as your standard that most closely resembles the protein you are assaying. BSA is a typical standards used to construct the curve.The bovine protein standard is the preferred standard in protein assays because in addition to its ability to increase signal in assays, bovine serum is affordable and easily mass-producible. Since cow blood is a widely available byproduct of the cattle industry, highly pure samples of bovine serum albumin are very accessible at a low cost. BSA offers features like sensitivity, compatibility with common substances in samples (i.e., detergents, etc.), standard curve linearity, and protein-protein variation for reliable, consistent results.

Also BSA's content of amino acid is average of the other protein and usually share the almost same components with others.